AT&T Classic Mail Voice Messaging System User Manual page 13

Your recorded directory name which callers
hear when there is no primary or alternate
greeting, or when they use the company
directorv.
A mailbox number which is identical to your
intercom number (if you have an intercom) or
a three-digit number beginning with 9.
Chapter 1: Before You Begin
Figure 1D: Elements
of your voice mail box
11